19-nor-delta-4-androstene, 3-one, 17-beta benzoate and method for manufacturing same



United States Patent 19-NOR-DELTA-4-ANDROSTENE, 3-ONE, 17-BETA BENZOATE AND METHOD FOR MANUFACTUR- DIG SAME Lawrence Hicks, Chicago, Ill., assiguor to Organics, Inc., Chicago, 111., a corporation of Illinois No Drawing. Application March 4, 1954, Serial No. 414,218

2 Claims. (Cl. 260-3974) This invention relates to the manufacture of 19-nordelta-4-androstene, 3-one, 17-beta benzoate (19-nor testosterone benzoate) and it is an object of this invention to produce and to provide a method for producing 19-nordelta-4-androstene, 3-one, 17-beta benzoate.

In my copending application Ser. No. 353,007, filed May 4, 1953, description is made of the manufacture of l9-Nor-delta-4-androstene, 3-one, 17-beta esters such as the propionate, cyclopentyl propionate, acetate, benzoate and the like and to methods for preparing same where the corresponding 17 01 is reacted for esterification with the corresponding acid anhydride or alkyl halide.

The androstene compounds and their derivatives generally exhibit two types of biological activitynamely, androgenic or male sex hormone activity and myotrophic or protein anabolic activity. In the use for treatment of conditions wherein myothrophic or protein anabolic activity is important, conjoint androgenic activity may not only be undesirable but more often is harmful to the extent that its presence will prohibit use of the particular steroid compound. This is particularly true in pediatrics and in geriatrics.

Many attempts have been made to isolate the desirable mytrophic or protein anabolic activity from the androgenie activity but elimination of the androgenic activity of androstane and androstene compounds generally results also in the lowering or loss also of the protein anabolic activity. The separation of the two types of activity becomes difiicult, especially in androstene steroidal compounds of the type described, yet it has been found that the build-up of the steroid molecule with certain groupings as distinguished from others enables such separation in a few instances in the production of a compound which has a high level of a desirable myotrophic activity without objectionable amounts of androgenic activity. A general pattern with respect to the types of groups or their location on the steroid molecule for the development of such results has not, to the present, been established. In the esters of l9-Nor-delta-4-androstene, 3-one, 17-beta 01, it has been found that the aliphatic esters such as the propionate, acetate, cyclopentyl propionate, valerate and the like have a high ratio of the undesirable androgenic activity with respect to'the desirable myotrophic or protein anabolic activity. It has been found, however, that the l9-Nor-delta-4-androstene, 3-one, l7-beta benzoate appears unexpectedly to be entirely unrelated to the aliphatic esters in that, unlike the aliphatic esters, the benzoate has a negligible amount of androgenic activity, yet its protein anabolic activity remains high enough so that an unexpectedly high ratio of anabolic activity to androgenic activity is secured.

Aside from these important dilferences in undesirable androgenic activity of which the benzoate is relatively free, the benzoate ester dilfers from the aliphatic esters also in the limitations with respect to the methods of manufacture and in the properties of the final compound. Where the aliphatic esters can be formed by reaction of the 17 ol with the corersponding acid anhydride or alkyl halide, the benzoic acid ester cannot be prepared in com mercially economical yields by reaction of the 17 01 with the alkyl halide. It seems that the reaction product that is formed comprises a mixture of the corresponding 17 benzoate with the enol dibenzoate from which separation of the 17 benzoate is difficult. With benzoic anhydride as the reactant for esterification, excellent yields of relatively pure benzoate can be secured which requires little, if any, purification as will become apparent "ice from the following procedure for the preparation of 19- Nor-delta-4-androstene, 3-one, 17-beta benzoate.

The benzoate appears also to differ from the corresponding aliphatic esters such as the acetate, propionate, cyclopentyl propionate and the valerate in the characteristics of the end product which is formed. The aliphatic esters all appear to form as a hydrate containing 1-1.5 moles of water of crystallization. The presence of this water of crystallization appears to make crystallization of the aliphatic esters difficult and they are therefore inclined to exist as amorphous, resinous substances. On the other hand, the benzoate is free of water of crystallization and forms readily into long needle-like crystals having a melting point of 174-l75 C. and a specific rotation at 20 in sodium light in percent ethanol of +104.5.

EXAMPLE 1 Preparation of 19-N0r-delta-4-androstene, 3-0ne, 17-beta-ol Three grams of estradiol-17-beta (0.011 mole; M. W. 272.4) was dissolved in 500 ml. of 2.5 N sodium hydroxide solution preferably with warming. To this mixture was added, dropwise at 0.5 degree C., 18.8 ml. (0.2 mole, 25.2 gm., M. W. 126) of dimethylsulfate with good agitation. After all of the dimethylsulfate was added, the mixture was allowed to warm to room temperature with stirring (2-3 hours) and then heated on a water bath (80-90 degrees C.) for one hour. The warm mixture was then diluted with two volumes of water and then cooled with scratching whereby crude methyl ether separated. This is washed well first with water and then by 70 percent methanol. Upon recrystallization from dilute ethanol, it melted at 120-121 degrees C.

17-beta estradiol-3-methyl ether (0.50 g., 0.0017 mole, M. P. 120-121 degrees) was added to the reaction flask, followed by 40 ml. of anhydrous ether. When complete solution of the solid had occurred, 50 ml. of anhydrous liquid ammonia was added with stirring, and 0.50 g. (0.072 mole) of lithium wire was immediately added in small pieces to the homogeneous solution, over a oneminute interval. The blue reaction mixture was stirred an additional ten minutes, then 4.6 g. (0.10 mole) of absolute ethanol was added dropwise over a ten to twenty minute interval with stirring when the foaming subsided. When the blue color had disappeared, most of the ammonia was evaporated by carefully heating on the steam bath, then ml. of cold water was added carefully to decompose the mixture. The aqueous layer was separated and extracted with four 15 ml. portions of ether. The combined solvent layers were washed with two 10 ml. port1ons of water, one 10 ml. portion of saturated sodium chloride solution, and were then dried over anhydrous potassium carbonate. The drying agent was removed by filtrat1ou and the residue obtained after distillation of the solvent was crystallized from thiophene-free benzene to yl ileldfiglsdihydroestradiol-17-beta-3-methyl ether. M. P.

To a solution of 220 mg. of the dihydro compound (M. P. 111.5l15.5 degrees) in 15 ml. of boiling methanol, was added over a three-minute period with swirling, a hot solution of 2.5 ml. of concentrated hydrochloric acid and 7.5 ml. of Water. The mixture was then allowed to cool slowly in a beaker of hot water over a period of one hour. After heating for a short time, the product was extracted with several portions of ether, the combined extract Washed with water, saturated sodium bicarbonate, water and dried over sodium sulfate. Removal of the solvent, recrystallization from methylcyclohexane conta1n1ng a small amount of ethyl acetate, and drying at 70 degrees (0.05 mm.) for two hours gave 19-nor-delta-4- androstene, 3-one, l7-beta-ol. M. P. l09.5-110.5 degrees.

EXAMPLE 2 Preparation of 19-N0r-delta-4-andr0stene, 3-0ne, 17-beta benzoate 27.4 grams (0.1 mole) of 19-Nor-delta-4-androstene, 3-one, 17-oeta-ol of Example 1 is dissolved in 500 cc. of anhydrous pyridine and 28.25 grams (0.125 mole) of benzoic anhydride added. The solution is refluxed for about four hours.

50cc..-ofdisti1led-.water::is then added and refluxing is continued ra addit onal.tQurhQu s,t c mpq e product willwcont i e c s nhydri e whichi d cult.

to eliminate; Onthe other hand, "if the material is hydrolyzed tobenzoicacid, the latter'is easily separated fromthe desired product.

The pyridine-water solution containing thesteroid'ester and free benzoic acid is distilled to a dry residue, and then taken up by solution in benzene. The benzene solution is Washed exhaustively with saturated sodium bicarbonatento free it of benzoic acid and itis then washed with 1 N'hydrochl'oricacid toffreeit of traces of pyridine.

The benzene solution is then exhaustively washed with water to free it'of mineral acid and it is then distilled to dryness. The dry. residue is dissolved in anhydrous ethanol by boiling under reflux-and thensufficicnt water is added :to .thealcohol solution-to reduce the concentration of the alcohol to 75" percent by volume. Upon cooling, the benzoate crystallizesin long needles. No recrystallization is believed to be necessary since the resulting product indicates substantial purity since the crystals have a melting point of 174-175 C. and a specificmotation pf,20.. C. at.104.5.

The.- yield f- ;the 19 -N0r-delta-4-androstene, 3-one,v

l7-beta benzoate rangesas'high; as 97 percent of theory.

It.has been;fo u nd that.;the compound .19-Nor-delta- 4-androstene, 3-one-,, l7-beta benzoate. .difiers. materially. fromthe other aliphaticiesters; both ,aslto activity and.

use and..inthe limitations with. respect: to manufacture and the properties thereof. available. from the ,benzoate have been unexpected but greatly beneficial in-the .use of benzoate' esters. ascompared tothe vpropionate or the cyclopentyl, propionate or-other aliphatic esters of .l9-Nor-testosterone. These differencesin activity. and results which have. been clearly established by animal;data; indicatethat the benzoate isvpractically void of androgenic activity whilesupplying a high degree of myotrophic or protein anabolic activity whereas thealiphatic esters such as the propionate, cyclopentyispropionate or valerate all show a comparatively high ratio. of androgenic activity; to myotrophic or pro-.

tein anabolic activity.

Aspreviously pointed out, high androgenic activity is undesirable in .thistypeof steroid, yet his, in general, difiicult to formulateaa steroid which offers. a vdesired protein anabolic activity without-supplying atleastsome amount of androgenic. activity. While the. aliphatic esters of l9-Nor-testosterone follow the general rule. and r have a high ratio ofandrogenic activity tomyotrophic or protein. anabolic activity, the l9-Nor-testosterone, benzoateappears. to ,be nonaanalogous in that a high- :degree ofprotein. anabolicactivity is secured practically in the absence of any androgenic activity.

Thishas been established by animal tests performed upon :rats in. which daily administrations were :made to castrated .male rats for seven consecutive days by subcutaneous injection to introduce a total of 7O0 fLg. of the various: esterscontained in corn oil as the .diluent.

The following table represents .results .which were.

secured as indicated by the growth rates of thevarious glands. Gain in weight of the ventral prostate gland The ditferences in reactions.

4 and seminal vesicles proves androgenic activity and gain n w ght p t e ..l v. or. anip swes. .my u nhicor pm: tein anabolic act1vity.

No. Body Ventral Seminal Levator of Treatment Weight Prostate Vesicles ani Rats m) s) e) e) 5 7 Oil only... 66. 5 11.0 8.6 i 15.9 5 19-Nor-testosterone 70 16.8 12.2. 39.1

benzoate, 700 pg. 5 l -Nor-testosterone 66 46.6 42.8 54.3

valerate, 700 [lg- 5 19-Nor-testosterone v 63 52.2 :4 51.7

propionate resin, 700 pg. 5 19-Nor-testosterone 65 54.8 45.0 48.4

propionate crystals, 700 g. 6 Testosterone 'propio- 66- 89.8" 99.9 42.4

nate, 700'pg.

For use as a measure intthe= trade;.theimportantyaluea constitutes, the ratio ofprotein anabolic; activity .to, an:;, drogenic activity which cangbe determined by the growth: of the levator ani to the ventral prostate.. Thisgratreg from the data secured above. is as -folloyvs-a 19-Nor-test0sterone benzoate" 4.000- l9-Nor-testosterone valerate 1.079 l9-Nor-testosterone propionate 0.802 Testosterone propionate 0.336-

From theseresults it will; be apparent that the; benzoate provides a very desirable,am ount'of activity. represented by growth of thelevator ani asicompared to the relatively. negligible growth of theventral prostate. On .thepther hand, the growth of the levator-ani .which gistseeured by, the aliphatic esters. is slightly greater inthe levator' ani with equivalent amountsof injection but theamountpfi growthin. the. ventral..prostate is even greater whiehindicates, that the aliphaticsestersimpart a high degree of androgenic activityv as compared .to thebenzoatezwith; a relatively small difference existing in the amount pf the proteinanabolic activity. Thisdiifierence is more noticeable in the ratioofthe gain in weightof .the levator ani as compared-to theventral prostate which indicates that the aliphatic esters impartandrogenic activity as No references .cited. 

1. THE COMPOUND 19-NOR-DELTA-4-ANDROSTENE, 3-ONE, 17-BETA BENZOATE. 